[thelist] MySQL oddness

r937 rudy at r937.com
Tue Jan 29 08:00:20 CST 2008


your "dodgy" sql is the problem, and will cause an error in version 5
which has stricter rules about evaluating joins

double-check your target server's version, because the dodgy sql should 
actually work on 4.1.22

you know how ANDs take precedence over ORs in compound conditions?

mixing JOIN syntax with the old "comma-separated table list" syntax is like
that

you have

    FROM snip_map_request `mr`
        , snip_course_details `c`
     INNER JOIN snip_course_details
          ON `c`.`id` = `mr`.`course_id`

notice where the comma is

this means that the following is parsed first --

         snip_course_details `c`
     INNER JOIN snip_course_details
          ON `c`.`id` = `mr`.`course_id`

and of course at this point you get the error about mr.course_id being
unknown

solution? rewrite all your joins so as not to use the (deprecated) old
"comma-separated table list" syntax


rudy
http://r937.com/






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